Physics Letters B (Dec 2016)
Shape coexistence from lifetime and branching-ratio measurements in 68,70Ni
- B.P. Crider,
- C.J. Prokop,
- S.N. Liddick,
- M. Al-Shudifat,
- A.D. Ayangeakaa,
- M.P. Carpenter,
- J.J. Carroll,
- J. Chen,
- C.J. Chiara,
- H.M. David,
- A.C. Dombos,
- S. Go,
- R. Grzywacz,
- J. Harker,
- R.V.F. Janssens,
- N. Larson,
- T. Lauritsen,
- R. Lewis,
- S.J. Quinn,
- F. Recchia,
- A. Spyrou,
- S. Suchyta,
- W.B. Walters,
- S. Zhu
Affiliations
- B.P. Crider
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824, USA; Corresponding author.
- C.J. Prokop
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824, USA; Department of Chemistry, Michigan State University, East Lansing, MI 48824, USA
- S.N. Liddick
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824, USA; Department of Chemistry, Michigan State University, East Lansing, MI 48824, USA
- M. Al-Shudifat
- Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996, USA; Department of Physics, Al al-Bayt University, Mafraq 25113, Jordan
- A.D. Ayangeakaa
- Physics Division, Argonne National Laboratory, Argonne, IL 60439, USA
- M.P. Carpenter
- Physics Division, Argonne National Laboratory, Argonne, IL 60439, USA
- J.J. Carroll
- U.S. Army Research Laboratory, Adelphi, MD 20783, USA
- J. Chen
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824, USA
- C.J. Chiara
- Oak Ridge Associated Universities Fellowship Program, U.S. Army Research Laboratory, Adelphi, MD 20783, USA
- H.M. David
- Physics Division, Argonne National Laboratory, Argonne, IL 60439, USA
- A.C. Dombos
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824, USA; Department of Physics, Michigan State University, East Lansing, MI 48824, USA
- S. Go
- Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996, USA
- R. Grzywacz
- Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996, USA; Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830, USA
- J. Harker
- Physics Division, Argonne National Laboratory, Argonne, IL 60439, USA; Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA
- R.V.F. Janssens
- Physics Division, Argonne National Laboratory, Argonne, IL 60439, USA
- N. Larson
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824, USA; Department of Chemistry, Michigan State University, East Lansing, MI 48824, USA
- T. Lauritsen
- Physics Division, Argonne National Laboratory, Argonne, IL 60439, USA
- R. Lewis
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824, USA; Department of Chemistry, Michigan State University, East Lansing, MI 48824, USA
- S.J. Quinn
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824, USA; Department of Physics, Michigan State University, East Lansing, MI 48824, USA
- F. Recchia
- Dipartimento di Fisica e Astronomia, Università degli Studi di Padova, I-35131 Padova, Italy
- A. Spyrou
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824, USA; Department of Physics, Michigan State University, East Lansing, MI 48824, USA
- S. Suchyta
- Department of Nuclear Engineering, University of California Berkeley, Berkeley, CA 94720, USA
- W.B. Walters
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA
- S. Zhu
- Physics Division, Argonne National Laboratory, Argonne, IL 60439, USA
- Journal volume & issue
-
Vol. 763
pp. 108 – 113
Abstract
Shape coexistence near closed-shell nuclei, whereby states associated with deformed shapes appear at relatively low excitation energy alongside spherical ones, is indicative of the rapid change in structure that can occur with the addition or removal of a few protons or neutrons. Near 68Ni (Z=28, N=40), the identification of shape coexistence hinges on hitherto undetermined transition rates to and from low-energy 0+ states. In 68,70Ni, new lifetimes and branching ratios have been measured. These data enable quantitative descriptions of the 0+ states through the deduced transition rates and serve as sensitive probes for characterizing their nuclear wave functions. The results are compared to, and consistent with, large-scale shell-model calculations which predict shape coexistence. With the firm identification of this phenomenon near 68Ni, shape coexistence is now observed in all currently accessible regions of the nuclear chart with closed proton shells and mid-shell neutrons.
